Parking lot management systems are known in several variations. EP 1 986 172 discloses a general reservation system in which identification data is read out via radio when entering and exiting. However, this publication does not provide for the reservation of specific parking spaces and also does not disclose any measures for increasing the functional reliability and the protection against manipulation or any measures for monitoring purposes. Publication US 2004/0068433 discloses a parking lot management and reservation system with a central computer, into which users can enter parking space reservations, e.g., via the Internet, and a camera at the entrance for reading the license numbers of the entering vehicles by means of optical character recognition (OCR) to open a barrier for vehicles that have parking space reservations. Parking attendants patrol the parking lot with mobile handheld devices that are connected to the central computer via radio and serve for randomly reading the license numbers of the parked vehicles by means of OCR to take action against parking violators. Although systems of this type reach a high degree of automation, they still require manual control processes and are also susceptible to incorrectly read, or even forged, license numbers.